This application claims the priority benefit of Taiwan application Ser. No. 87120424, filed Dec. 9, 1998, the full disclosure of which is incorporated herein by reference.
1. Field of Invention
The present invention relates to a network connection device. More particularly, the present invention relates to an automatic network connection device capable of correctly wiring the device to a network cable.
2. Description of Related Art
As computer technologies continue to advance, many computers in one general location are often linked together to form a local area network. At present, Ethernet is the most common networking configuration. Several types of drop wires are used for connecting to various terminals in an Ethernet. Two of the most common types of wires include the coaxial cable and the twisted pair wires. Due to some advantages of twisted pair wires over coaxial cables, more twisted pairs are now used for connecting to an Ethernet. For example, the 10M/100M Base T has two pairs of twisted wires inside the cable. In other words, there are altogether four wires inside a cable. The device discussed in this invention is an automatic network connection device mostly used for the connection of terminals to the twisted pairs in an Ethernet.
FIG. 1 shows a conventional method of linking up network connection devices by a twisted pair cable. As shown in FIG. 1, one of the two networking devices 110 and 120 can be a client""s computer terminal while the other one can be a hub in the network or simply other devices connected to the network. The network cable 130 has at least four strands of wires, internally. The four wires inside the network cable 130 are connected to the four signaling terminals of each networking device, respectively.
Specifically, the four wires inside the cable 130 are connected to a positive receiving terminal RX+, a negative receiving terminal RXxe2x88x92, a positive transmission terminal TX+ and a negative transmission terminal TXxe2x88x92, respectively. In fact, the positive receiving terminal RX+ and the negative receiving terming RXxe2x88x92 together form a differential receiver circuit. Similarly, the positive transmission terminal TX+ and the negative transmission terminal TXxe2x88x92 together form a differential transmitter circuit. Hence, each terminal of the networking devices 110 and 120 must be correctly wired together through network cable 130.
For example, the positive transmission terminal TX+ of the networking device 110 must be wired to the positive receiving terminal RX+ of the networking device 120 and the negative transmission terminal TXxe2x88x92 of the networking device 110 must be wired to the negative receiving terminal RXxe2x88x92 of the networking device 120. Similarly, the positive transmission terminal TX+ of the networking device 120 must be wired to the positive receiving terminal RX+ of the networking device 110 and the negative transmission terminal TXxe2x88x92 of the networking device 120 must be wired to the negative receiving terminal RXxe2x88x92 of the networking device 110.
Therefore, in constructing a network system, wire-matching a time-consuming process. Four wires have to be connected per user terminal and each of the wires must be carefully labeled. Normally, the job has to be done by network technicians because each of the four wires within a network cable must be connected to the correct terminal in each network connection device. If any pair of the wires is accidentally mixed up, a related part of the network may malfunction and hence may require lengthy trouble-shooting.
In light of the foregoing, there is a need to design an automatic wiring device for simplifying network cable connection.
Accordingly, the purpose of the present invention is to provide a network connection device for automatic wiring. The network connection device can pick up the correct wire inside a network cable and connect to appropriate terminals of the device without human intervention. Hence, labor can be saved and human errors can be greatly reduced.
To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a network connection device for automatic wiring. The network connection device includes an interface circuit, a switching array and a controlling circuit.
The controlling circuit is coupled to the interface circuit and the switching array responsible for overseeing the entire network connection.
The switching array has a first group of connecting terminals and a second group of connecting terminals. Each group of terminals has four terminal points. Connection between the terminal points in the first group and the terminal points in the second group is achieved by internal circuitry. The actual connection is made by the signals delivered from the controlling circuit. The first group of terminals is connected to a network cable. The network cable houses four wires so that each terminal points in the first group is connected to one of the four wires inside a network cable.
The interface circuit has a positive receiving terminal, a negative receiving terminal, a positive transmitting terminal and a negative transmitting terminal. Each of these terminals is connected to a terminal point of the second terminal group of the switching array. The controlling circuit is able to receive or transmit data through the interface circuit.
The method of operating the aforementioned network connection device for connecting to a network cable is as follows. First, as soon as the network connection device is physically connected to the wires inside a network cable, a signal is emitted from the controlling circuit to the switching array requesting that the positive receiving terminal and the negative receiver terminal of the interface circuit be connected to a pair of signal-carrying wires inside the cable. Next, the controlling circuit picks up the signals from the positive receiving terminal and the negative receiving terminal to determine if the polarity of the two wires are correctly made. If proper polarity is made, nothing changes.
However, if the polarity of the wiring connection is incorrect, the controlling circuit signals the switching array to swap their connection. Thereafter, the controlling circuit sends a signal to the switching array so that the positive transmitting terminal and the negative transmitting terminal are connected to a pair of unattached wires inside the network cable. Subsequently, a packet is send from the controlling circuit to the network cable through the positive transmitting terminal and the negative transmitting terminal. The controlling circuit then waits for an acknowledgement packet from the network cable through the positive receiving terminal and the negative receiving terminal. On receiving the acknowledgement packet regarding the polarity connection to the network cable, a proper controlling signal can be sent to the switching array. If the original connection is judged to be in error, wiring connections from the positive transmitting terminal and negative transmitting terminal to the wires inside the network cable can be swapped.
According to one preferred embodiment of this invention, the device further includes a media-independent interface (MII) circuit. The MII circuit resides within the controlling circuit and acts as a communicative link between the controlling circuit and the interface circuit. When the positive receiving terminal and the negative receiving terminal are correctly wired to the network cable, the MII circuit emits four bits of xe2x80x981xe2x80x99 in sequence to the controlling circuit. Alternatively, when the positive receiving terminal and the negative receiving terminal are incorrectly wired to the network cable, the MII circuit emits four bits of xe2x80x980xe2x80x99 in sequence to the controlling circuit.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.